Which of the following combinations will produce a 0.4 m nacl solution?

a) mixing 500 ml of 0.4 m naoh with 500 ml of 0.4 m hcl
b) mixing 300 ml of 1.2 m naoh with 600 ml of 0.6 m hcl
c) mixing 500 ml of 0.4 m nacl solution with 500 ml water
d) diluting 400 ml of 0.6 m nacl with water to a final volume of 1.0 l

Option C: Mixing 500 mL of 0.4 M NaCl solution with 500 mL water

Explanation:

0.4M is [NaCl]

Molar concentration which means moles of solute in 1L.

How many moles, do we have in our volume of 500 mL

Molarity . volume = mole

0.4 mol/L . 0.5L = 0.2 mole

(remember convert mL to L)

This 0.2 mole of NaCl that were in 500 mL, are also in 500 mL of water, so In 1L of water, I have the double of mole, so 0.4M

it's c. elements are placed in rows based on how may valencies electrons have.

a compound is a molecule made of atoms from different elements.

a. by the combination of an unlimited number of elements